Explain how the F_DUPFD_CLOEXEC fcntl command might be useful.
What will be an ideal response?
he ?ag is useful in the prevention of leaking ?le descriptors in multithreaded programs. Assume one thread is duplicating a ?le descriptor by calling dup and about to set the close-on-exec ?ag using fcntl.Ifanother thread calls exec after the call to dup returns, but beforethe call to fcntl is made, then the new program executed will have access to a ?le descriptor which the original program had intended to prevent. The F_DUPFD_CLOEXEC ?ag closes this window,making the duplicating of the ?le descriptor and the setting of the closeon-exec ?ag an atomic operation
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Managers can apply tests to a field of data in a table or query to identify trends using the ________ function
Fill in the blank(s) with correct word
Mary is writing a program that repeatedly prompts the user for an inventory number and displays a message stating whether on not the object is in stock. What sort of control structure(s) will she need to include in her program?
a. repetition and selection b. selection and sequential c. repetition and sequential d. repetition, selection, and sequential